Systems, catheters, drive units, and methods for automatic catheter identification

ABSTRACT

A catheter for an ultrasound system can a marker disposed on the hub. The marker is optically or magnetically readable and, when read, identifies the catheter. A drive unit can include an optical or magnetic marker reader. Alternatively or additionally, a catheter may include an active memory arrangement that can be read by an appropriate reader on the drive unit.

TECHNICAL FIELD

The present disclosure is directed to the area of intravascularultrasound imaging systems and methods of making and using the systems.The present disclosure is also directed to intravascular ultrasoundimaging systems that include arrangements for automatic catheteridentification when the catheter is attached to a drive unit.

BACKGROUND

Intravascular ultrasound (“IVUS”) imaging systems have proven diagnosticcapabilities for a variety of diseases and disorders. For example, IVUSimaging systems have been used as an imaging modality for diagnosingblocked blood vessels and providing information to aid medicalpractitioners in selecting and placing stents and other devices torestore or increase blood flow. IVUS imaging systems have been used todiagnose atheromatous plaque build-up at particular locations withinblood vessels. IVUS imaging systems can be used to determine theexistence of an intravascular obstruction or stenosis, as well as thenature and degree of the obstruction or stenosis. IVUS imaging systemscan be used to visualize segments of a vascular system that may bedifficult to visualize using other intravascular imaging techniques,such as angiography, due to, for example, movement (e.g., a beatingheart) or obstruction by one or more structures (e.g., one or more bloodvessels not desired to be imaged). IVUS imaging systems can be used tomonitor or assess ongoing intravascular treatments, such as angiographyand stent placement in real (or almost real) time. Moreover, IVUSimaging systems can be used to monitor one or more heart chambers.

IVUS imaging systems have been developed to provide a diagnostic toolfor visualizing a variety of diseases or disorders. An IVUS imagingsystem can include a control module (with a pulse generator, an imageprocessor, and a monitor), a drive unit, a catheter, and one or moretransducers disposed in the catheter. The transducer-containing cathetercan be positioned in a lumen or cavity within, or in proximity to, aregion to be imaged, such as a blood vessel wall or patient tissue inproximity to a blood vessel wall. The pulse generator in the controlmodule generates electrical pulses that are delivered to the one or moretransducers and transformed to acoustic signals that are transmittedthrough patient tissue. Reflected pulses of the transmitted acousticsignals are absorbed by the one or more transducers and transformed toelectric pulses. The transformed electric pulses are delivered to theimage processor and converted to an image displayable on the monitor.

BRIEF SUMMARY

One aspect is a catheter for an ultrasound system that includes acatheter sheath defining a lumen; a hub coupled to the catheter sheathand configured for attachment to a motor drive; an elongated, rotatabledriveshaft disposed within the lumen of the catheter sheath andextending into the hub, the driveshaft having a proximal end and adistal end, wherein the proximal end is configured and arranged forcoupling to the motor drive for rotating the driveshaft; an imagingdevice coupled to the distal end of the driveshaft with rotation of thedriveshaft causing a corresponding rotation of the imaging device, theimaging device including at least one transducer configured and arrangedfor transforming applied electrical signals to acoustic signals and alsofor transforming received echo signals to electrical signals; at leastone conductor extending from the hub through the lumen of the cathetersheath and coupled to the imaging device for carrying the electricalsignals; and a marker disposed on the hub, wherein the marker isoptically or magnetically readable and, when read, identifies thecatheter.

In at least some aspects, the marker is optically readable. In at leastsome aspects, the marker includes a one- or two-dimensional code. In atleast some aspects, the marker includes a barcode or QR code.

In at least some aspects, the marker is magnetically readable. In atleast some aspects, the marker includes a strip with informationmagnetically encoded thereon.

In at least some aspects, the marker is printed onto the hub. In atleast some aspects, the marker is adhered to the catheter with anadhesive. In at least some aspects, the marker is disposed on a rotatingportion of the hub.

In at least some aspects, the marker, when read, identifies a type ofthe catheter. In at least some aspects, the marker, when read,identifies a serial number of the catheter. In at least some aspects,the marker, when read, identifies an expiration date of the catheter.

In at least some aspects, the marker extends around a full circumferenceof the hub. In at least some aspects, the marker is disposed onnon-curved surface of the hub.

Another aspect is an ultrasound system that includes any of thecatheters described above; and a drive unit coupleable to the catheter.The drive unit includes a drive hub configured for attachment to the hubof the catheter; a rotation mechanism configured for rotating thedriveshaft of the catheter; and a marker reader configured to opticallyor magnetically read the marker on the catheter to identify thecatheter.

In at least some aspects, the ultrasound system further includes aprocessor coupleable to the drive unit and configured for identifyingthe catheter from the marker when read by the marker reader. In at leastsome aspects, the processor is further configured for altering orsetting one or more settings of the ultrasound system in response to theidentification of the catheter.

Another aspect is a drive unit for an ultrasound system that includes adrive hub configured for attachment to a catheter; a rotation mechanismconfigured for rotating a driveshaft of the catheter; and a readerconfigured to optically or magnetically read a marker on the catheter toidentify the catheter.

In at least some aspects, the reader is an optical reader. In at leastsome aspects, the reader is a magnetic reader.

Yet another aspect is a catheter for an ultrasound system that includesa catheter sheath defining a lumen; a hub coupled to the catheter sheathand configured for attachment to a motor drive; an elongated, rotatabledriveshaft disposed within the lumen of the catheter sheath andextending into the hub, the driveshaft having a proximal end and adistal end, wherein the proximal end is configured and arranged forcoupling to the motor drive for rotating the driveshaft; an imagingdevice coupled to the distal end of the driveshaft with rotation of thedriveshaft causing a corresponding rotation of the imaging device, theimaging device including at least one transducer configured and arrangedfor transforming applied electrical signals to acoustic signals and alsofor transforming received echo signals to electrical signals; at leastone conductor extending from the hub through the lumen of the cathetersheath and coupled to the imaging device for carrying the electricalsignals; and an active memory arrangement disposed on the hub, whereinthe active memory arrangement is configured for transferring informationusing a single conductor and is configured to store information thatidentifies the catheter.

Another aspect is an ultrasound system that includes any of thecatheters described above; and a drive unit coupleable to the catheter.The drive unit includes a drive hub configured for attachment to the hubof the catheter; a rotation mechanism configured for rotating thedriveshaft of the catheter; and a reader configured to obtain theinformation from the active memory arrangement on the catheter toidentify the catheter.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present invention aredescribed with reference to the following drawings. In the drawings,like reference numerals refer to like parts throughout the variousfigures unless otherwise specified.

For a better understanding of the present invention, reference will bemade to the following Detailed Description, which is to be read inassociation with the accompanying drawings, wherein:

FIG. 1 is a schematic view of one embodiment of an intravascularultrasound imaging system;

FIG. 2 is a schematic side view of one embodiment of a catheter of anintravascular ultrasound imaging system;

FIG. 3 is a schematic perspective view of one embodiment of a distal endof the catheter shown in FIG. 2 with an imaging core disposed in a lumendefined in the catheter;

FIG. 4A is a schematic perspective view of one embodiment of a cathetercoupled to a drive unit of an intravascular ultrasound imaging system;

FIG. 4B is a schematic block diagram of one embodiment of a drive unit;

FIG. 5 is a schematic side view of one embodiment of a portion of acatheter with a marker on the hub of the catheter;

FIG. 6 is a schematic side view of another embodiment of a portion of acatheter with a marker on the hub of the catheter;

FIG. 7 is a schematic perspective view of a third embodiment of aportion of a catheter with a marker on the hub of the catheter;

FIG. 8 is a schematic side view of one embodiment of a portion of adrive unit with a marker reader; and

FIG. 9 is a schematic perspective view of a fourth embodiment of aportion of a catheter with a marker on a rotating portion of the hub ofthe catheter, the housing of the hub in FIG. 9 is partially transparentto illustrate components of the hub within the housing including therotating portion of the hub and the marker.

DETAILED DESCRIPTION

The present disclosure is directed to the area of intravascularultrasound imaging systems and methods of making and using the systems.The present disclosure is also directed to intravascular ultrasoundimaging systems that include arrangements for automatic catheteridentification when the catheter is attached to a drive unit.

Suitable intravascular ultrasound (“IVUS”) imaging systems include, butare not limited to, one or more transducers disposed on a distal portionof a catheter configured and arranged for percutaneous insertion into apatient. Examples of IVUS imaging systems with catheters are found in,for example, U.S. Pat. Nos. 7,306,561; and 6,945,938; as well as U.S.Patent Application Publication Nos. 20060253028; 20070016054;20070038111; 20060173350; and 20060100522, all of which are incorporatedherein by reference.

FIG. 1 schematically shows one embodiment of an IVUS imaging system 100.The IVUS imaging system 100 includes a catheter 102 that is coupleableto a control module 104. The control module 104 may include, forexample, a processor 106, a pulse generator 108, a drive unit 110, andone or more displays 112. In at least some embodiments, the pulsegenerator 108 forms electric signals that are input to one or moretransducers (312 in FIG. 3) disposed in the catheter 102. In at leastsome embodiments, electric signals transmitted from the one or moretransducers (312 in FIG. 3) is input to the processor 106 forprocessing. The processed electric signals from the one or moretransducers (312 in FIG. 3) may be displayed as one or more images onthe one or more displays 112. In at least some embodiments, mechanicalenergy from the drive unit 110 is used to drive an imaging core (306 inFIG. 3) disposed in the catheter 102. For example, the drive unit 110can be used to rotate the imaging core or to pullback the imaging corealong vasculature of the patient or any combination thereof. In at leastsome embodiments, the drive unit 110 is spatially separated from theother components of the control module 104 and may be coupled to theprocessor using a cord or other wired arrangement or by wirelessconnection.

The processor 106 may also be used to control the functioning of one ormore of the other components of the control module 104. For example, theprocessor 106 may be used to control at least one of the frequency orduration of the electrical signals transmitted from the pulse generator108, the rotation rate of the imaging core (306 in FIG. 3) by the driveunit 110, the velocity or length of the pullback of the imaging core(306 in FIG. 3) by the drive unit 110, or one or more properties of oneor more images formed on the one or more displays 112.

FIG. 2 shows, in schematic side view, one embodiment of the catheter 102of the IVUS imaging system (100 in FIG. 1). The catheter 102 includes anelongated member 203 and a hub 204. The elongated member 203 includes aproximal portion 206 and a distal portion 208. In FIG. 2, the proximalportion 206 of the elongated member 203 is coupled to the catheter hub204 and the distal portion 208 of the elongated member is configured andarranged for percutaneous insertion into a patient. In at least someembodiments, the catheter 102 defines at least one flush port, such asflush port 210. In at least some embodiments, the flush port 210 isdefined in the hub 204. In at least some embodiments, the hub 204 isconfigured and arranged to couple to the drive unit (110 in FIG. 1). Insome embodiments, the elongated member 203 and the hub 204 are formed asa unitary body. In other embodiments, the elongated member 203 and thehub 204 are formed separately and subsequently assembled together. Inaddition, as described in more detail below, the catheter 102 can alsoinclude a marker 211 which, when read, can identify the catheter. Forexample, the marker 211 can identify the type of the catheter (using,for example, an identification code or a name or any other suitableidentification information) or can include a serial number for thecatheter or any other catheter identification information or anycombination thereof.

FIG. 3 shows, in schematic perspective view, one embodiment of thedistal portion 208 of the elongated member 203 of the catheter 102. Theelongated member 203 includes a sheath 302 and a lumen 304. An imagingcore 306 is disposed in the lumen 304. The imaging core 306 includes animaging device housing 308 coupled to a distal end of a transducerconnection system, such as a drive cable or driveshaft 309.

The sheath 302 may be formed from any flexible, biocompatible materialsuitable for insertion into a patient. Examples of suitable materialsinclude, for example, polyethylene, polyurethane, plastic, spiral-cutstainless steel, nitinol hypotube, and the like or combinations thereof.

One or more transducers 312 may be mounted to the imaging device housing308 and employed to transmit and receive acoustic signals. In apreferred embodiment (as shown in FIG. 3), an array of transducers 312are mounted to the imaging device housing 308. In other embodiments, asingle transducer may be employed. In yet other embodiments, multipletransducers in an irregular-array may be employed. Any number oftransducers 312 can be used. For example, there can be one, two, three,four, five, six, seven, eight, nine, ten, twelve, fifteen, sixteen,twenty, twenty-five, fifty, one hundred, five hundred, one thousand, ormore transducers. As will be recognized, other numbers of transducersmay also be used.

The one or more transducers 312 may be formed from one or more knownmaterials capable of transforming applied electrical signals to pressuredistortions on the surface of the one or more transducers 312, and viceversa. Examples of suitable materials include piezoelectric ceramicmaterials, piezocomposite materials, piezoelectric plastics, bariumtitanates, lead zirconate titanates, lead metaniobates,polyvinylidenefluorides, and the like.

The pressure distortions on the surface of the one or more transducers312 form acoustic signals of a frequency based on the resonantfrequencies of the one or more transducers 312. The resonant frequenciesof the one or more transducers 312 may be affected by the size, shape,and material used to form the one or more transducers 312. The one ormore transducers 312 may be formed in any shape suitable for positioningwithin the catheter 102 and for propagating acoustic signals of adesired frequency in one or more selected directions. For example,transducers may be disc-shaped, block-shaped, rectangular-shaped,oval-shaped, and the like. The one or more transducers may be formed inthe desired shape by any process including, for example, dicing, diceand fill, machining, microfabrication, and the like.

As an example, each of the one or more transducers 312 may include alayer of piezoelectric material sandwiched between a conductive acousticlens and a conductive backing material formed from an acousticallyabsorbent material (e.g., an epoxy substrate with tungsten particles).During operation, the piezoelectric layer may be electrically excited byboth the backing material and the acoustic lens to cause the emission ofacoustic signals.

In at least some embodiments, the one or more transducers 312 can beused to form a radial cross-sectional image of a surrounding space.Thus, for example, when the one or more transducers 312 are disposed inthe catheter 102 and inserted into a blood vessel of a patient, the onemore transducers 312 may be used to form an image of the walls of theblood vessel and tissue surrounding the blood vessel.

In at least some embodiments, the imaging core 306 is rotated about alongitudinal axis of the catheter 102. As the imaging core 306 rotates,the one or more transducers 312 emit acoustic signals in differentradial directions. When an emitted acoustic signal with sufficientenergy encounters one or more medium boundaries, such as one or moretissue boundaries, a portion of the emitted acoustic signal is reflectedback to the emitting transducer as an echo signal. Each echo signal thatreaches a transducer with sufficient energy to be detected istransformed to an electrical signal in the receiving transducer. The oneor more transformed electrical signals are transmitted to the controlmodule (104 in FIG. 1) where the processor 106 processes theelectrical-signal characteristics to form a displayable image of theimaged region based, at least in part, on a collection of informationfrom each of the acoustic signals transmitted and the echo signalsreceived. In at least some embodiments, the rotation of the imaging core306 is driven by the drive unit 110 (FIG. 1).

As the one or more transducers 312 rotate about the longitudinal axis ofthe catheter 102 emitting acoustic signals, multiple images are formedthat collectively form a radial cross-sectional image of a portion ofthe region surrounding the one or more transducers 312, such as thewalls of a blood vessel of interest and the tissue surrounding the bloodvessel. In at least some embodiments, the radial cross-sectional imagecan be displayed on one or more displays 112.

In at least some embodiments, the imaging core 306 may also move axiallyalong the blood vessel within which the catheter 102 is inserted so thata plurality of cross-sectional images may be formed along an axiallength of the blood vessel. In at least some embodiments, during animaging procedure the one or more transducers 312 are retracted (i.e.,pulled back) along the longitudinal length of the catheter 102. In atleast some embodiments, the catheter 102 includes at least onetelescoping section that can be retracted during pullback of the one ormore transducers 312. In at least some embodiments, the drive unit 110drives the pullback of the imaging core 306 within the catheter 102. Inat least some embodiments, the drive unit 110 pullback distance of theimaging core is at least 5 cm. In at least some embodiments, the driveunit 110 pullback distance of the imaging core is at least 10 cm. In atleast some embodiments, the drive unit 110 pullback distance of theimaging core is at least 15 cm. In at least some embodiments, the driveunit 110 pullback distance of the imaging core is at least 20 cm. In atleast some embodiments, the drive unit 110 pullback distance of theimaging core is at least 25 cm.

The quality of an image produced at different depths from the one ormore transducers 312 may be affected by one or more factors including,for example, bandwidth, transducer focus, beam pattern, as well as thefrequency of the acoustic signal. The frequency of the acoustic signaloutput from the one or more transducers 312 may also affect thepenetration depth of the acoustic signal output from the one or moretransducers 312. In general, as the frequency of an acoustic signal islowered, the depth of the penetration of the acoustic signal withinpatient tissue increases. In at least some embodiments, the IVUS imagingsystem 100 transmits acoustic signals centered at an operationalfrequency. The operational frequency is typically within a range of 5MHz to 60 MHz. The acoustic signals may be transmitted within afrequency bandwidth that includes the operational frequency.

In at least some embodiments, the one or more transducers 312 may bemounted to the distal portion 208 of the imaging core 306. The imagingcore 306 may be inserted in the lumen of the catheter 102. In at leastsome embodiments, the catheter 102 (and imaging core 306) are insertedpercutaneously into a patient via an accessible blood vessel, such asthe femoral artery, at a site remote from a target imaging location. Thecatheter 102 may then be advanced through patient vasculature to thetarget imaging location, such as a portion of a selected blood vessel.

As discussed above, the driveshaft 309 couples the imaging devicehousing 308 to the drive unit (110 in FIG. 1). In at least someembodiments, one or more transducer conductors 314 electrically couplethe one or more transducers 312 to the control module (104 in FIG. 1).

FIG. 4A shows, in perspective view, one embodiment of a catheter 102coupled to a drive unit 110. The catheter 102 includes an elongatedmember 203 (e.g., catheter sheath) and a hub 204. As shown in FIG. 4A,the hub 204 of the catheter 102 is coupled to the drive unit 110 withthe elongated member 203 extending outward from the drive unit 110. Asdescribed above, the drive unit 110 can be coupled to one or more othercomponents of an IVUS imaging system, such as a pulse generator, aprocessor, a display, or the like.

Any suitable drive unit can be used. FIG. 4B is a block diagramillustrating one example of components that can be part of a drive unit110. It will be recognized that a drive unit may include more or fewercomponents and may include one or more additional components. In theembodiment of FIG. 4B, the drive unit 110 includes a hub 416 forcoupling to the catheter, a rotation mechanism 418 for rotating thedriveshaft of the catheter, a pullback mechanism 420 for pulling backthe driveshaft of the catheter during the imaging procedure, and asignal transmission unit 422 that conveys signals (drive signals orultrasound response signals) between the catheter and a pulse generatoror processor of the IVUS imaging system. In addition, as described inmore detail below, the drive unit 110 can include a reader 424, such asan optical or magnetic reader.

Drive units are typically reusable and can be compatible with a varietyof different catheters 102. The different catheters that are compatiblewith a drive unit may house transducers having different operationalfrequencies at which the transducers operate or other differentoperational settings or differences. It is useful if the drive unit 110,and associated processor 106 (FIG. 1), can automatically determine whichtype of catheter 102 is attached to the drive unit 110.

In one commercial embodiment, the identification of the catheter typeincludes the catheter having a small printed circuit (PC) board withshort, opens, or diodes between three pads on the board. The PC board isconnected to the motor drive 102 through spring pins on the PC board(and part of the catheter) that connect it through the motor drive 102to the processor 106 (FIG. 1) which “reads” the code, identifies thecatheter 102, and adjusts settings appropriate to the catheter type.This arrangement, however, may be prone to error arising fromcontamination of the spring pins or motor drive connector, insufficienttravel in the spring pins, or saline contamination of the PC board ormotor drive connector creating shorts between the pads that canmisinterpreted as the wrong catheter ID code.

Instead of this pin/PC board combination, a marker 211 can be applied tothe exterior of the catheter hub, as illustrated in FIG. 2, and can beread or scanned by the system (for example, the drive unit) as thecatheter hub 204 is coupled to the drive unit. In at least someembodiments, it may be possible to retrofit existing catheters or driveunits to include the marker and reader, respectively. The marker 211 canbe used to identify the catheter. For example, the marker 211 canidentify the type of the catheter (using, for example, an identificationcode or a name or any other suitable identification information) or caninclude a serial number for the catheter or any other catheteridentification information or any combination thereof. In at least someembodiments, the ultrasound system can use this identificationinformation for settings for the system or to limit or provide systemfeatures based on the identification of the catheter or otherwise usethe identification to facilitate operation or use of the catheter.

In at least some embodiments, the marker 211 may also include anexpiration date or other shelf-life or expiration information. In atleast some embodiments, the system may prevent or limit use or reuse ofthe catheter or provide a warning to the user regarding the expiration,or any combination of these actions if the expiration date has passedwhen the catheter is coupled to the drive unit.

FIG. 5 illustrates one embodiment of a marker 211 attached to the hub204 of a catheter 102. The marker 211 can be, for example, aone-dimension or two-dimensional code that can be optically ormagnetically read. For example, the marker 211 can be a barcode, a QRcode, or any other suitable code that can be optically read. Forexample, such a marker 211 could be laser-printed, pad-printed, heatstamped, adhesively adhered, or otherwise attached, inscribed, orpositioned onto the hub 204.

FIG. 6 illustrates another embodiment of a marker 211 in the form ofmultiple circumferential rings (or portions of rings) that can beoptically or magnetically read. For example, such a marker 211 could belaser-printed, pad-printed, heat stamped, adhesively adhered, orotherwise attached or inscribed onto the hub 204.

The marker 211 could be a magnetic stripe or any other suitable magneticmarker which can be read magnetically. The magnetic strip can be adheredor otherwise attached to the hub using an adhesive or any other suitablemethod.

The marker 211 can be a 1-Wire™ memory arrangement (such as thoseavailable from Maxim Integrated, San Jose, Calif.) or other activememory arrangement on which the identification of the catheter isstored. The 1-Wire™ memory arrangement provides for low-speed datatransfer over a single conductor using a communication protocol. Thecorresponding reader in this embodiment would be a reader capable ofobtaining information from the 1-Wire™ or other active memoryarrangement.

FIG. 7 illustrates another embodiment in which the marker 211 ispositioned on a flat (e.g., non-curved) surface of the hub 204 of thecatheter 102 instead of a cylindrical or curved surface, as illustratedin FIGS. 5 and 6.

FIG. 8 illustrates the drive unit 110 with a corresponding reader 424.The reader can be any suitable optical or magnetic reader including, butnot limited to, a camera, a CCD (charge-coupled device) array, magneticstripe reader, 1-Wire™ or other active memory, or any other suitablereader. In at least some embodiments, the reader 424 of the drive unit110 may have a processor or memory that can identify the catheter byreading the marker 211 and provide that identification to the processor106 (FIG. 1) of the control module 104 (FIG. 1). In at least someembodiments, the reader 424 of the drive unit 110 produces signals asthe reader 424 reads these markers and these signals are delivered tothe processor 106 (FIG. 1) of the control module 104 (FIG. 1) which thenidentifies the catheter. In at least some embodiments, uponidentification of the catheter the processor 106 or other components ofthe system automatically sets one or more system settings based on theidentification of the catheter. In at least some embodiments, the systemmay limit or provide access to system functions or features based on theidentification of the catheter.

In at least some embodiments, fully attaching the hub 204 of thecatheter 102 with the drive unit 110 (for example, engaging the driveunit and rotating the hub to a final, locked position) aligns the marker211 with the reader 424. In at least some embodiments, the hub 204 ofthe catheter 102 can be inserted or otherwise attached to the drive unit110 in any orientation and the reader 424 of the drive unit can bearranged to read the marker 211 as the hub of the catheter or drive unitrotates to fully engage. In at least some embodiments, the rotation ofthe hub 204 of the catheter 102 or drive unit 110 can facilitate readingof the marker 211, such as, for example, reading a bar code.

In at least some embodiments, the reader 424 may be arranged to read themarker 211 regardless of the orientation of the marker relative to thedrive unit 110. For example, a barcode or circumferential rings (see,for example, the embodiment illustrated in FIG. 6) may be positionedentirely around a circumference (or at least 50%, 66%, 75%, 80%, 90%,95% or more of the circumference) to facilitate reading the markerregardless of the orientation of the marker relative to the drive unit.In at least some embodiments, there may be one or more gaps in thebarcode or circumferential rings so that the barcode or circumferentialrings do not extend entirely around the circumference, but ratherincludes one or more interruptions (i.e., gaps) around the ring. In atleast some embodiments, properly engaging the hub 204 of the catheter102 with the drive unit 110 (for example, as illustrated in theembodiments illustrated in FIGS. 7 and 8) aligns the marker 211 with thereader 424.

In at least some embodiments, if the marker 211 cannot be read or doesnot provide the expected information or produces an error, the systemmay direct the user to disengage and recouple the catheter 102 to thedrive unit 110 so that the marker 211 can be reread. The system mayalert the user if there are multiples read failures and the user may berequested to manually enter the catheter information.

In at least some embodiments, the marker 211 can be attached to arotating portion of the catheter so that the rotational motion canfacilitate reading of the marker. FIG. 9 illustrates one embodiment of ahub 204 of a catheter 102 with a housing 930 (which, FIG. 9, ispartially transparent in order to view components in the interior of thehousing) and a rotating hub portion 932 that couples to the driveshaft309 (FIG. 3) of the catheter and, when the catheter is coupled to thedrive unit 110 (FIG. 4), couples to the rotation mechanism 418 (FIG. 4)of the drive unit. In this embodiment, the reader 424 (FIG. 4) of thedrive unit 110 (FIG. 4) is positioned within the drive unit so that thereader 424 can read the marker when the catheter is coupled to the driveunit. In at least some embodiments, the rotation of the rotating hubportion 932 of the catheter 102 during operation or testing of thesystem can facilitate reading of the marker 211, such as, for example,reading a bar code. For example, the marker 211 can be a one-dimensionalbar code that can be read as the rotating hub portion 932 is rotated bythe rotation mechanism 418 (FIG. 4) of the drive unit 110 (FIG. 4)

The above specification and examples provide a description of theinvention and the manufacture and use of the invention. Since manyembodiments of the invention can be made without departing from thespirit and scope of the invention, the invention also resides in theclaims hereinafter appended.

What is claimed as new and desired to be protected by Letters Patent ofthe United States is:
 1. A catheter for an ultrasound system, thecatheter comprising: a catheter sheath defining a lumen; a hub coupledto the catheter sheath and configured for attachment to a motor drive;an elongated, rotatable driveshaft disposed within the lumen of thecatheter sheath and extending into the hub, the driveshaft having aproximal end and a distal end, wherein the proximal end is configuredand arranged for coupling to the motor drive for rotating thedriveshaft; an imaging device coupled to the distal end of thedriveshaft with rotation of the driveshaft causing a correspondingrotation of the imaging device, the imaging device comprising at leastone transducer configured and arranged for transforming appliedelectrical signals to acoustic signals and also for transformingreceived echo signals to electrical signals; at least one conductorextending from the hub through the lumen of the catheter sheath andcoupled to the imaging device for carrying the electrical signals; and amarker disposed on the hub, wherein the marker is optically ormagnetically readable and, when read, identifies the catheter.
 2. Thecatheter of claim 1, wherein the marker is optically readable.
 3. Thecatheter of claim 1, wherein the marker comprises a one- ortwo-dimensional code.
 4. The catheter of claim 1, wherein the markercomprises a barcode or QR code.
 5. The catheter of claim 1, wherein themarker is magnetically readable.
 6. The catheter of claim 1, wherein themarker comprises a strip with information magnetically encoded thereon.7. The catheter of claim 1, wherein the marker is printed onto the hub.8. The catheter of claim 1, wherein the marker is disposed on a rotatingportion of the hub.
 9. The catheter of claim 1, wherein the marker, whenread, identifies a type of the catheter.
 10. The catheter of claim 1,wherein the marker, when read, identifies a serial number of thecatheter.
 11. The catheter of claim 1, wherein the marker, when read,identifies an expiration date of the catheter.
 12. The catheter of claim1, wherein the marker is disposed on non-curved surface of the hub. 13.An ultrasound system, comprising: the catheter of claim 1; and a driveunit coupleable to the catheter, the drive unit comprising: a drive hubconfigured for attachment to the hub of the catheter; a rotationmechanism configured for rotating the driveshaft of the catheter; and amarker reader configured to optically or magnetically read the marker onthe catheter to identify the catheter.
 14. The ultrasound system ofclaim 13, further comprising a processor coupleable to the drive unitand configured for identifying the catheter from the marker when read bythe marker reader.
 15. The ultrasound system of claim 14, wherein theprocessor is further configured for altering or setting one or moresettings of the ultrasound system in response to the identification ofthe catheter.
 16. A drive unit for an ultrasound system, the drive unitcomprising: a drive hub configured for attachment to a catheter; arotation mechanism configured for rotating a driveshaft of the catheter;and a reader configured to optically or magnetically read a marker onthe catheter to identify the catheter.
 17. The drive unit of claim 16,wherein the reader is an optical reader.
 18. The drive unit of claim 16,wherein the reader is a magnetic reader.
 19. A catheter for anultrasound system, the catheter comprising: a catheter sheath defining alumen; a hub coupled to the catheter sheath and configured forattachment to a motor drive; an elongated, rotatable driveshaft disposedwithin the lumen of the catheter sheath and extending into the hub, thedriveshaft having a proximal end and a distal end, wherein the proximalend is configured and arranged for coupling to the motor drive forrotating the driveshaft; an imaging device coupled to the distal end ofthe driveshaft with rotation of the driveshaft causing a correspondingrotation of the imaging device, the imaging device comprising at leastone transducer configured and arranged for transforming appliedelectrical signals to acoustic signals and also for transformingreceived echo signals to electrical signals; at least one conductorextending from the hub through the lumen of the catheter sheath andcoupled to the imaging device for carrying the electrical signals; andan active memory arrangement disposed on the hub, wherein the activememory arrangement is configured for transferring information using asingle conductor and is configured to store information that identifiesthe catheter.
 20. An ultrasound system, comprising: the catheter ofclaim 19; and a drive unit coupleable to the catheter, the drive unitcomprising: a drive hub configured for attachment to the hub of thecatheter; a rotation mechanism configured for rotating the driveshaft ofthe catheter; and a reader configured to obtain the information from theactive memory arrangement on the catheter to identify the catheter.